.btn-back {
    font: 14px/27px Arial,Helvetica,sans-serif;
    color: #fff;
    text-decoration: none;

    position: relative;
    display: block;
    position: relative;
    top: 8%;
}
/*按钮主体*/
.btn-back span {
    display: inline-block;
    font-size: 13px;
    line-height: 27px;
    height: 27px;
    padding: 0 10px 0 5px;
    background: -moz-linear-gradient(top, #5bbfd8, #449fb6);
    background: -webkit-linear-gradient(top, #5bbfd8, #449fb6);
    border: 1px solid #2c96b2;
    border-left: 0;
    border-radius: 2px 5px 5px 2px;
    text-shadow: 0 -1px 0 rgba(0, 0, 0, .4);

    margin-left: 12px;
    position: relative;
    z-index: 2;
}
/*左边的小三角*/
.btn-back:before {
    content: '';
    display: inline-block;
    width: 20px;
    height: 20px;
    background: -moz-linear-gradient(-45deg, #5bbfd8, #449fb6);/*背景旋转-45&deg;*/
    background: -webkit-linear-gradient(-45deg, #5bbfd8, #449fb6);
    border: 1px solid #2c96b2;
    -webkit-transform-origin: 0 0;/*设置基点为0,0*/
    -moz-transform-origin: 0 0;
    -webkit-transform: scaleX(0.8) rotate(45deg);/*X轴压缩，旋转45&deg;*/
    -moz-transform: scaleX(0.8) rotate(45deg);
    border-radius: 3px 2px;

    position: absolute;
    left: 18px;
    top: 0px;
}